diff options
Diffstat (limited to 'fs/cifs/cifsencrypt.c')
-rw-r--r-- | fs/cifs/cifsencrypt.c | 146 |
1 files changed, 129 insertions, 17 deletions
diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c index 35042d8f7338..89fb94fac4b5 100644 --- a/fs/cifs/cifsencrypt.c +++ b/fs/cifs/cifsencrypt.c @@ -27,6 +27,7 @@ #include "md5.h" #include "cifs_unicode.h" #include "cifsproto.h" +#include "ntlmssp.h" #include <linux/ctype.h> #include <linux/random.h> @@ -42,7 +43,7 @@ extern void SMBencrypt(unsigned char *passwd, const unsigned char *c8, unsigned char *p24); static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu, - const struct mac_key *key, char *signature) + const struct session_key *key, char *signature) { struct MD5Context context; @@ -78,7 +79,7 @@ int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server, server->sequence_number++; spin_unlock(&GlobalMid_Lock); - rc = cifs_calculate_signature(cifs_pdu, &server->mac_signing_key, + rc = cifs_calculate_signature(cifs_pdu, &server->session_key, smb_signature); if (rc) memset(cifs_pdu->Signature.SecuritySignature, 0, 8); @@ -89,7 +90,7 @@ int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server, } static int cifs_calc_signature2(const struct kvec *iov, int n_vec, - const struct mac_key *key, char *signature) + const struct session_key *key, char *signature) { struct MD5Context context; int i; @@ -145,7 +146,7 @@ int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server, server->sequence_number++; spin_unlock(&GlobalMid_Lock); - rc = cifs_calc_signature2(iov, n_vec, &server->mac_signing_key, + rc = cifs_calc_signature2(iov, n_vec, &server->session_key, smb_signature); if (rc) memset(cifs_pdu->Signature.SecuritySignature, 0, 8); @@ -156,14 +157,14 @@ int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server, } int cifs_verify_signature(struct smb_hdr *cifs_pdu, - const struct mac_key *mac_key, + const struct session_key *session_key, __u32 expected_sequence_number) { unsigned int rc; char server_response_sig[8]; char what_we_think_sig_should_be[20]; - if ((cifs_pdu == NULL) || (mac_key == NULL)) + if (cifs_pdu == NULL || session_key == NULL) return -EINVAL; if (cifs_pdu->Command == SMB_COM_NEGOTIATE) @@ -192,7 +193,7 @@ int cifs_verify_signature(struct smb_hdr *cifs_pdu, cpu_to_le32(expected_sequence_number); cifs_pdu->Signature.Sequence.Reserved = 0; - rc = cifs_calculate_signature(cifs_pdu, mac_key, + rc = cifs_calculate_signature(cifs_pdu, session_key, what_we_think_sig_should_be); if (rc) @@ -209,7 +210,7 @@ int cifs_verify_signature(struct smb_hdr *cifs_pdu, } /* We fill in key by putting in 40 byte array which was allocated by caller */ -int cifs_calculate_mac_key(struct mac_key *key, const char *rn, +int cifs_calculate_session_key(struct session_key *key, const char *rn, const char *password) { char temp_key[16]; @@ -262,6 +263,90 @@ void calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt, } #endif /* CIFS_WEAK_PW_HASH */ +/* This is just a filler for ntlmv2 type of security mechanisms. + * Older servers are not very particular about the contents of av pairs + * in the blob and for sec mechs like ntlmv2, there is no negotiation + * as in ntlmssp, so unless domain and server netbios and dns names + * are specified, there is no way to obtain name. In case of ntlmssp, + * server provides that info in type 2 challenge packet + */ +static int +build_avpair_blob(struct cifsSesInfo *ses) +{ + struct ntlmssp2_name *attrptr; + + ses->tilen = 2 * sizeof(struct ntlmssp2_name); + ses->tiblob = kzalloc(ses->tilen, GFP_KERNEL); + if (!ses->tiblob) { + ses->tilen = 0; + cERROR(1, "Challenge target info allocation failure"); + return -ENOMEM; + } + attrptr = (struct ntlmssp2_name *) ses->tiblob; + attrptr->type = cpu_to_le16(NTLMSSP_DOMAIN_TYPE); + + return 0; +} + +/* Server has provided av pairs/target info in the type 2 challenge + * packet and we have plucked it and stored within smb session. + * We parse that blob here to find netbios domain name to be used + * as part of ntlmv2 authentication (in Target String), if not already + * specified on the command line. + * If this function returns without any error but without fetching + * domain name, authentication may fail against some server but + * may not fail against other (those who are not very particular + * about target string i.e. for some, just user name might suffice. + */ +static int +find_domain_name(struct cifsSesInfo *ses) +{ + unsigned int attrsize; + unsigned int type; + unsigned int onesize = sizeof(struct ntlmssp2_name); + unsigned char *blobptr; + unsigned char *blobend; + struct ntlmssp2_name *attrptr; + + if (!ses->tilen || !ses->tiblob) + return 0; + + blobptr = ses->tiblob; + blobend = ses->tiblob + ses->tilen; + + while (blobptr + onesize < blobend) { + attrptr = (struct ntlmssp2_name *) blobptr; + type = le16_to_cpu(attrptr->type); + if (type == NTLMSSP_AV_EOL) + break; + blobptr += 2; /* advance attr type */ + attrsize = le16_to_cpu(attrptr->length); + blobptr += 2; /* advance attr size */ + if (blobptr + attrsize > blobend) + break; + if (type == NTLMSSP_AV_NB_DOMAIN_NAME) { + if (!attrsize) + break; + if (!ses->domainName) { + struct nls_table *default_nls; + ses->domainName = + kmalloc(attrsize + 1, GFP_KERNEL); + if (!ses->domainName) + return -ENOMEM; + default_nls = load_nls_default(); + cifs_from_ucs2(ses->domainName, + (__le16 *)blobptr, attrsize, attrsize, + default_nls, false); + unload_nls(default_nls); + break; + } + } + blobptr += attrsize; /* advance attr value */ + } + + return 0; +} + static int calc_ntlmv2_hash(struct cifsSesInfo *ses, const struct nls_table *nls_cp) { @@ -321,7 +406,8 @@ calc_exit_2: return rc; } -void setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf, +int +setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf, const struct nls_table *nls_cp) { int rc; @@ -333,25 +419,48 @@ void setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf, buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME)); get_random_bytes(&buf->client_chal, sizeof(buf->client_chal)); buf->reserved2 = 0; - buf->names[0].type = cpu_to_le16(NTLMSSP_DOMAIN_TYPE); - buf->names[0].length = 0; - buf->names[1].type = 0; - buf->names[1].length = 0; + + if (ses->server->secType == RawNTLMSSP) { + if (!ses->domainName) { + rc = find_domain_name(ses); + if (rc) { + cERROR(1, "error %d finding domain name", rc); + goto setup_ntlmv2_rsp_ret; + } + } + } else { + rc = build_avpair_blob(ses); + if (rc) { + cERROR(1, "error %d building av pair blob", rc); + return rc; + } + } /* calculate buf->ntlmv2_hash */ rc = calc_ntlmv2_hash(ses, nls_cp); - if (rc) + if (rc) { cERROR(1, "could not get v2 hash rc %d", rc); + goto setup_ntlmv2_rsp_ret; + } CalcNTLMv2_response(ses, resp_buf); /* now calculate the MAC key for NTLMv2 */ hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context); hmac_md5_update(resp_buf, 16, &context); - hmac_md5_final(ses->server->mac_signing_key.data.ntlmv2.key, &context); + hmac_md5_final(ses->server->session_key.data.ntlmv2.key, &context); - memcpy(&ses->server->mac_signing_key.data.ntlmv2.resp, resp_buf, + memcpy(&ses->server->session_key.data.ntlmv2.resp, resp_buf, sizeof(struct ntlmv2_resp)); - ses->server->mac_signing_key.len = 16 + sizeof(struct ntlmv2_resp); + ses->server->session_key.len = 16 + sizeof(struct ntlmv2_resp); + + return 0; + +setup_ntlmv2_rsp_ret: + kfree(ses->tiblob); + ses->tiblob = NULL; + ses->tilen = 0; + + return rc; } void CalcNTLMv2_response(const struct cifsSesInfo *ses, @@ -365,6 +474,9 @@ void CalcNTLMv2_response(const struct cifsSesInfo *ses, hmac_md5_update(v2_session_response+8, sizeof(struct ntlmv2_resp) - 8, &context); + if (ses->tilen) + hmac_md5_update(ses->tiblob, ses->tilen, &context); + hmac_md5_final(v2_session_response, &context); /* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */ } |